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Objective: To investigate the effects of normal aging on motor imagery vividness and working memory., Design: Descriptive study with 3 groups., Setting: Laboratory of a university-affiliated research rehabilitation center., Participants: A sample of healthy persons (N=80) divided into 3 age groups: young (26+/-5.0 y), intermediate (53.6+/-5.4 y), and elderly (67.6+/-4.6 y)., Interventions: Not applicable., Main Outcome Measures: The kinesthetic and visual imagery scores of the Kinesthetic and Visual Imagery Questionnaire and scores from 3 domains of working memory (visuospatial, kinesthetic, verbal)., Results: Results revealed that visual motor imagery scores were higher than kinesthetic scores (imagery effect: P=.001); however, there was also a significant imagery x group interaction (P=.017). Post hoc analyses showed that only the young and intermediate groups had higher visual than kinesthetic motor imagery scores (P=.005 and .001, respectively), indicating a loss of visual motor imagery dominance in the elderly group. There was no group effect (P=.963) signifying that the level of motor imagery vividness was comparable between age groups. Significant decreases (17.3% and 22.5%, respectively) in visuospatial working memory scores were found in the intermediate (P=.011) and elderly (P=.001) groups, whereas a significant reduction (P=.01) in kinesthetic working memory scores was observed only in the elderly group (26.7%). There was also an age-related significant decline of visuospatial (r= -.50) and kinesthetic (r=-.34) working memory., Conclusions: The level of motor imagery vividness does not diminish with age, but the quality changes. The dominance of visual motor imagery lessens with aging resulting in motor imagery modality-equivalence. These motor imagery alterations are associated with an age-related decline in visuospatial and kinesthetic working memory., (Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Objective: To examine the reproducibility of 2 chronometric tests: time-dependent motor imagery (TDMI) screening test and temporal congruence test., Design: Test-retest 10 to 14 days apart., Setting: Laboratory of a university-affiliated center for research in rehabilitation., Participants: Twenty persons post cerebrovascular accident (CVA) and 46 healthy persons (controls)., Intervention: The reproducibility of the TDMI screening test, wherein the number of stepping movements (performed in sitting) imagined over 15, 25, and 45 seconds is recorded, and of the temporal congruence test wherein the duration of physically executed (E) and imagined (I) stepping movements is recorded, was evaluated., Main Outcome Measures: The test-retest reliability of the number of imagined movements (TDMI screening test), movement duration and I/E time ratios (temporal congruence test), and intrasession reliability of the temporal congruence test were assessed by using intraclass correlation coefficients (ICCs)., Results: For the TDMI screening test, the ICCs ranged from .88 to .93 (CVA, n=20) and from .87 to .92 (controls, n=9). For the temporal congruence test, when the total duration of 2 series of 5 stepping movements was averaged, ICCs ranged from .76 to .97 (CVA, n=20) and from .77 to .93 (controls, n=46), whereas for 1 series the ICCs ranged from .71 to .95 and from .63 to .95 in the CVA and control groups, respectively. The ICCs for intrasession reliability for the CVA (n=20) and control (n=46) groups, respectively, ranged from .90 to .98 and .95 to .97., Conclusions: The present findings support the reproducibility of both tests in both groups. Mental chronometry can be used reliably for the screening of patients capable of motor imagery or for measuring temporal congruence between real and imagined movements poststroke.

Objective: To examine the relationship between working memory and motor improvement obtained after a single training session combining mental and physical practice., Design: Before-after trial., Setting: Laboratory of a university-affiliated research rehabilitation center., Participants: A sample of 12 patients with stroke and 14 age- and gender-matched healthy subjects., Intervention: In a single session, patients were trained with combined mental and physical practice to increase the loading on the affected leg while standing up and sitting down., Main Outcome Measures: Motor improvement as measured by the percentage change in limb loading on the affected limb after training and 24 hours later (follow-up), and the relationship between working memory and percentage motor improvement., Results: The loading on the affected leg was improved after training (P< .01) and at follow-up (P< .05), and working memory scores at follow-up correlated significantly (P< .004 to P< .007) with the level of improvement. The visuospatial domain yielded the strongest correlation (r= .83), followed by the verbal (r= .62) and kinesthetic (r= .59) domains., Conclusions: These results suggest that the outcome (improved limb loading) of mental rehearsal with motor imagery depends on the ability to maintain and manipulate information in working memory.

Objectives: To study the stretch reflex excitability (spasticity) of the plantarflexor muscles during gait in patients with hemiparesis and to study the relationships of spasticity during gait with spasticity at rest and gait speed., Design: Cross-sectional, descriptive., Setting: Rehabilitation center., Participants: Convenience sample of 30 patients (58 +/- 11yr) with hemiparesis (<6mo poststroke) and 15 healthy controls (59 +/- 8yr)., Interventions: Patients walked at natural speed, healthy subjects at very slow speed for 10 gait cycles. Electromyographic activation of the medial gastrocremius was recorded by using surface electrodes. A 2-dimensional video camera system with reflective markers was used to acquire kinematics of the lower limbs., Main Outcome Measures: Electromyography-lengthening velocity slopes, calculated from measures obtained during the lengthening periods of the medial gastrocnemius muscle during the stance and the swing phases. Measured spatisticity (Modified Ashworth Scale [MAS]), static strength (ankle clonus), and motor control (Fugl-Meyer test)., Results: Velocity-sensitive electromyographic responses, indicative of hyperactive stretch reflexes, were found on the paretic side during the stance phase of gait (in 66% of the patients), but not on the nonparetic side or in controls. In many patients, velocity-sensitive responses coexisted with low plantarflexor activation levels during the stance phase. No clear patterns of response were measured during the swing phase in either group. Spasticity during gait in the patients was found to be positively related (r = .47, p < .01; r = .57, p < .001) to spasticity at rest (MAS; ankle clonus), whereas it was found to be negatively related to gait speed (r = -.47 to -.53, p < .01)., Conclusions: The validity of the present method is supported by the fact that it is locomotor-specific and that it allowed for a good discrimination between spastic and nonspastic limbs, as well as between stance and swing phases of the gait cycle. The results also support plantarflexor spasticity as a factor contributing to the poor locomotor performance after stroke., (Copyright 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation)

For many patients with damage to the central nervous system (CNS), execution of motor tasks is very difficult, sometimes impossible, even after early participation in an active rehabilitation program. Several investigators have recently proposed that mental practice could be used by these patients as a therapeutic tool to improve their performance of motor functions, yet very little empirical work addresses this issue directly. This article discusses the rationale for investigating mental practice as a means of promoting motor recovery in patients with a neurologic disorder. We first present evidence supporting the existence of a similarity between executed and imagined actions using data from psychophysical, neurophysiologic, and brain imaging studies. This parallel is then extended to the repetition of movements during physical and mental practice of a motor skill. Finally, a new model is proposed to emphasize the key role of motor imagery as an essential process of mental practice, and also to stimulate additional research on this type of training in the rehabilitation of patients with motor impairments of cerebral origin.

Objective: To evaluate the immediate and retention effects of a 4-week training program on the performance of locomotor-related tasks in chronic stroke., Design: Randomized, controlled pilot study with 2-month follow-up., Setting: Rehabilitation center., Subjects: A convenience sample consisting of 12 chronic stroke subjects was used. Subjects were randomly assigned to the experimental or the control group. Three subjects withdrew from the study., Intervention: Both experimental and control groups participated in exercise classes three times a week for 4 weeks. The exercise class for the experimental group focused on strengthening the affected lower limb and practicing functional tasks involving the lower limbs, while the control group practiced upper-limb tasks., Main Outcome Measures: Lower-limb function was evaluated by measuring walking speed and endurance, peak vertical ground reaction force through the affected foot during sit-to-stand, and the step test., Results: The experimental group demonstrated significant immediate and retained (2-month follow-up) improvement (p < or = .05) compared with the control group in walking speed and endurance, force production through the affected leg during sit-to-stand, and the number of repetitions of the step test., Conclusion: The pilot study provides evidence for the efficacy of a task-related circuit class at improving locomotor function in chronic stroke.

Objective: To measure the contribution of passive stiffness to the ankle plantarflexor moment during gait in subjects with hemiparesis early after stroke. The relationship of passive stiffness with gait speed was also examined., Design: Cross-sectional, descriptive., Patients and Other Participants: A sample of convenience of 14 patients (54.7+/-10.9 yrs) with a hemiparesis for less than 5 months and 11 healthy controls (50.6+/-11.6 yrs)., Main Outcome Measures: The contribution of passive stiffness to the plantarflexor moment during gait was obtained using moment-angle slope (stiffness) values. Total plantarflexor stiffness was measured during gait, and passive stiffness was measured during passive dorsiflexion imposed by an isokinetic dynamometer at velocities and ranges of movement matched with values recorded during the plantarflexor lengthening period of the stance phase. The contribution of passive stiffness was obtained by dividing the passive stiffness (dynamometer) by the total plantarflexor stiffness (gait)., Results: On the paretic side, passive stiffness contributed more (16.8%; range 2.9% to 49.6%) to total plantarflexor stiffness during gait compared (p<.01) with both the nonparetic side (7.3%) and control values (5.9%). This increased contribution on the paretic side resulted from a large muscle-tendon passive stiffness, a decreased active muscle contribution, or both. Although in some patients the increased passive component led to the development of a total plantarflexor stiffness that was within normal values, it did not in others either because the active component was very small or because limited dorsiflexion during the stance phase prevented the passive component tension to develop. The contribution of passive stiffness was not significantly (p>.05) related to gait speed in both the patients and the controls., Conclusions: The increased contribution of passive stiffness to total plantarflexor moment during gait likely acts as an adaptation for a defective muscle active component, helping ankle push-off at the end of the stance phase. Although this mechanism is effective in most of the patients, it cannot come into action if the dorsiflexion movement during the stance phase is prevented, for instance, by enhanced stretch reflexes.

Objective: To assess the effects of acetic acid iontophoresis (AAI) and ultrasound on calcifying tendinitis of the shoulder, and to determine the relation between changes in the radiological measures of calcium deposit (CD) and shoulder function., Design: Randomized control trial., Setting: General community, private practice., Patients: Twenty-two adults (7 men, 15 women) with a calcifying tendinitis of the shoulder, without associated conditions, stratified according to the type of lesions (X-ray: type I, fleecy appearance: type II, homogeneous), were randomly allocated to an experimental (EXP, n = 11) or to a control (CTL, n = 10) group., Interventions: CTL group, no treatment; EXP group, nine treatments including AAI (5% acetic acid solution via the negative electrode, 5mA galvanic current, 20 minutes) followed by continuous ultrasound (0.8w/cm2, 1MHz, 5 minutes)., Main Outcome Measures: Area and density of the CD, passive shoulder abduction (range of motion [ROM]), pain intensity., Results: Significant reduction in the area and density of CD (ANCOVA, p = .01 and .03) over time in the EXP and CTL groups, but no significant difference between groups for any of the variables measured. The decrease in the area of CD in type I lesions (n = 5) was larger (Mann-Whitney U test, p < .01) than in type II (n = 16) lesions. The relation was stronger (rs = .90) between changes in area and density of CD than between ROM and pain (rs = -.67). Correlations were weak (rs = .21 to .41) between radiological and functional changes., Conclusion: The reduction in CD area and density likely results from a natural process rather than treatment (AAI and ultrasound); type I lesions (resorptive phase) are more likely to display resorption of the CD than type II lesions (formative phase). Reduction of the CD area does not necessary result in a functional improvement.

This study compared the measurements of the Motor Assessment Scale (MAS) to that of the Fugl-Meyer Assessment (FMA), a reliable and valid test for motor function in stroke patients. Thirty-two patients (20 men, 12 women) with a mean age of 60 years, and a mean time since stroke of 64.5 days, were tested with the FMA and MAS on two consecutive days. The Spearman correlation coefficient for total FMA and total MAS scores was 0.96. For selected items, significant (p < 0.001) correlations ranged from 0.65 to 0.93, except for sitting balance (-0.10). Low negative correlations between sitting balance scores and other items (motor and sensation) were found only for the FMA test, suggesting that the FMA sitting balance test is not valid for measuring balance and is likely responsible for the low correlation. Comparison of scores (normalized in percent of maximal value) for corresponding items of the two instruments also indicated that the FMA measured a higher (Wilcoxon = p < 0.0001) level of motor recovery, (especially in more disabled patients), for both the upper (15.7%) and lower extremities (27.5%). Lastly, a cumulative frequency distribution analysis indicated that a larger proportion of patients was found in the lower class interval scores of the MAS in comparison to the FMA. These results (1) support the concurrent validity of the MAS for measuring motor recovery in acute stroke patients; (2) demonstrate the poor validity of the FMA sitting balance test, and (3) suggest that the FMA scale can better discriminate the level of motor recovery than the MAS in the early stage of recovery or in the more disabled subjects.

The efficacy of an early, intensive, supervised rehabilitation program to accelerate knee strength recovery in the first 3 weeks postmeniscectomy by arthroscopy was evaluated using a randomized controlled trial design. The maximal voluntary isokinetic strength of 31 men, randomly allocated to either a treatment (EXP) or a control (CTL) group, was measured twice by a blind rater: preoperatively (pretest) and 3 weeks postsurgery (posttest), using a computer-controlled Kin-Com dynamometer (Chattecx Corporation, Chattanooga, TN). Strength deficits of the operated leg at the pretest and posttest were established in percent of the values obtained for the sound leg at the pretest. In the interval between the surgery and the posttest, the patients of the EXP group (n = 15) received nine supervised treatments combined to home exercises whereas patients of the control group (n = 16) had no specific physiotherapy treatment but were given instructions in postsurgical management and prescribed exercises by the orthopedic surgeons. Patients of the EXP group had better knee extensor strength recovery than patients of the CTL group (ANCOVA, p < 0.001). The size of the strength difference (3 weeks postsurgery) between EXP and CTL subgroups (n = 8) matched according to preoperative deficits was as large as 26% and the residual deficits of the untreated patients were two to three times larger than those of the treated patients. The results of this study highlight the importance of instituting an early intensive and supervised rehabilitation program, especially for workers returning to a strenuous job requiring good knee extensor muscle function.

A randomized controlled pilot trial was conducted to estimate the effects of early, intensive, gait-focused physical therapy on ambulatory ability in acute, stroke patients. Twenty-seven patients with middle cerebral artery infarct of thromboembolic origin confirmed by computed axial tomography scan were stratified and randomly assigned to the experimental group, to a control group that received early, intensive and conventional therapy, or to a group receiving routine conventional therapy that started later and was not intense. Assessments at entry, six weeks, and three and six months by independent evaluators permitted comparisons with reference to clinical measures of motor performance, balance, and functional capacity, and laboratory measures of gait movements. Group results at six weeks demonstrated that gait velocity was similar in the two conventional groups thereby eliminating the timing of the interventions as an important factor. At that point, gait velocity was faster in the experimental group. The difference translated into a moderate effect size of 0.58. The time dedicated to gait training but not to total therapy time was correlated (rs = 0.63) to gait velocity. This effect disappeared at three and six months after stroke. These pilot results justify planning a large trial to test the effectiveness of a therapeutic protocol that focuses on early and intense gait therapy in an effort to facilitate early ambulation following stroke.

Effects of vibratory stimulation and maximal isometric contraction on a fine motor control task were evaluated in 17 human subjects. Electromyographic audiovisual feedback cues derived from two fine-wire bipolar electrodes, inserted to a depth of 12 and 6 mm respectively, were used to train the subjects to isolate a motor unit in the extensor carpi radialis brevis muscle. A specially designed compressed air driven vibrator providing vibratory stimulation with an amplitude of 2 mm and a frequency range of 120-160 cycles per second was applied to the muscle tendon. A significant decrease was found in the subjects; ability to isolate the pretest motor unit during and after continuous and interrupted periods of vibration and following a maximal isometric contraction of the extensor carpi radials brevis muscle. Individual variations in the subjects' responses to the forms of application of the vibratory stimulus, electrode preference and feedback specificity were observed. Results suggest that marked spatial recruitment of motor units, brought into action by the vibration stimulus or by the maximal isometric contraction, interfered with inhibitory mechanisms necessary to achieve isolation and control of a single motor unit. A therapeutic application of vibration, based on the marked spatial recruitment observed during and after vibration, is proposed for muscle reeducation.